Journal of Physical Studies 16(1/2), Article 1902 [19 pages] (2012)
DOI: https://doi.org/10.30970/jps.16.1902

PHOTOIONIZATION MODELLING OF PLANETARY NEBULAE WITH THE DUST GRAINS PRESENCE. I. THE IMPACT OF THE GRAIN PRESENCE ON THE EMISSION SPECTRUM

B. Ya. Melekh¹, A. R. Kuzmak²
¹Department for Astrophysics, Ivan Franko National University of Lviv
8, Kyrylo and Mefodiy St., Lviv, UA--79005, Ukraine,
² Department for Theoretical Physics, Ivan Franko National University of Lviv,
12, Drahomanov St., Lviv, UA--79005, Ukraine

The review of the theoretical basis for photoionization modelling of the planetary nebulae (PNe) envelopes in the presence of grains is given. The photoionization models (PhM) grid for the Milky Way (MW) PNe was calculated along the evolutionary tracks of their central stars in the assumption of the black body ionizing spectrum shape. The outer radius was calculated as a function of the age and expansive velocity of the PN envelope. The inner radius was calculated in the assumption of constant density over volume in PNe envelopes [R. Szczerba, Astron. Astrophys. {\bf 181}, 365 (1987)]. For each selected point at the evolution track the subgrid of PhM was calculated for the following free parameters: PNe envelope mass as well as the kind and abundance of grains. We used the following kinds of grains during PhM calculations: carbonaceous grains, silicate grains, and carbonaceous grains with molecules of polycyclic aromatic hydrocarbon (PAH) (10\%). The relative chemical abundance (A/H) of the gas was assumed the same over nebular volume for all grid models and it corresponds to the averaged one for PNe in MW. The impact of the grain presence on the model predicted spectrum of PNe was analyzed.

PACS number(s): 98.38.Ly, 98.58.Li, 98.58.Ay, 98.38Bn, 97.20.Rp